NMR of Nuclei near a Paramagnetic Impurity in Crystals

We report a new experimental NMR technique of wide applicability wherein the NMR of nuclei at crystalline sites near a localized paramagnetic impurity is directly observed. We find this method useful in determining electron-nuclear interactions and crystal structure, and as a site-selective probe of spin lattice relaxation, spin diffusion, and dynamic polarization processes for nuclei. We have applied this technique to Y${\left({\mathrm{C}}_2{\mathrm{H}}_5\mathrm{S}{\mathrm{O}}_4\right)}_3$·9${\mathrm{H}}_2$O doped with ${\mathrm{Yb}}^{3+}$ and ${\mathrm{Nd}}^{3+}$, Ca${\mathrm{F}}_2$:${\mathrm{Eu}}^{2+}$, and N${\mathrm{H}}_4$Cl:${\mathrm{Cu}}^{2+}$(2${\mathrm{H}}_2$O).